Design, Selection and Arrangement of Sprinkler Irrigation System

Sprinkler for Irrigation and Its Design

The sprinkler is the most important part of the sprinkler irrigation system.  Water with pressure sprays into the air through it, scatters into small droplets and sprays evenly in the planting area.

Anyou irrigation believes that the selection and arrangement of sprinklers in the design of sprinkler irrigation system is a key factor affecting the quality of irrigation water in the whole irrigation system. When selecting sprinkler, besides considering its own performance, such as working pressure, flow rate, range radius, combined sprinkler irrigation intensity and adjustable sprinkler sector angle, Anyou Irrigation also takes into account of factors such as permissible sprinkler irrigation intensity of soil, size and shape of plot, lawn varieties, water source conditions and user requirements .

In addition, in the same irrigation group of the same project or one project, it is better to choose a sprinkler with similar type or performance, so as to facilitate the control of irrigation uniformity and the operation and management of the whole system.

The arrangement of sprinklers in sprinkler irrigation system includes the combination of sprinklers, the spacing of sprinklers along branch pipes and the spacing of branch pipes. The rationality of sprinkler arrangement is directly related to the quality of irrigation water in the whole system.

 Sprinkler Types and Selection in Sprinkler Irrigation System

Anyou Irrigation provides many kinds of sprinklers, which are divided into small range sprinklers of 0.6-6 meters, medium range sprinklers of 5-13 meters, medium range sprinklers of 9-18 meters and large range sprinklers of more than 20 meters.

Small range micro sprinkler can be divided into Rotating micro sprinkler and Misting Micro sprinkler according to the way of effluent. Installation ways are divided into standing type and hanging type. The spraying radius of these Anyou sprinklers is 0.6m, 1m, 2m, 3m and 6m. Various spraying forms and adjustable angle nozzles can be selected, and has high sprinkler irrigation intensity. It is not only suitable for small irrigation, but also for shrub and hedge irrigation, dust cleaning, and temperature reducing. Most of these nozzles are “matched irrigation intensity nozzles”. That is to say, their irrigation intensity is basically the same whether it is full circle spraying, semi-circle spraying or 90 degrees and other angles. This characteristic is very advantageous to ensure the uniformity of spraying system.For example , the Anti insect sprinkler of Anyou Irrigation Ay-1119 has 5 nozzle sizes, which are 1.0mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2.0mm.This design makes the flow rate of micro-sprinkler reach 42L/H to 213 L/H, which meets various needs of farmers.

Most of the small and medium range sprinklers are impact sprinklers, such as Anyou sprinkler AY-5003 ,Anyou sprinkler AY-5022 , with a range of 5-12 meters, These sprinklers are suitable for sprinkler irrigation of medium-sized green space and shrubs ,vegetables and flowers.

Especially the rotary sprinkler of Anyou AY-5205 , with a range of 8-13meters, with its unique spraying method and incomparable water-saving characteristics, especially suitable for sloping land and new planting spraying.

Most of the middle range sprinklers are rotary sprinklers, such as Anyou irrigation AY-5105, AY-5030P, AY-5104A,etc. These irrigation sprinklers can be divided into plastic sprinklers and metal sprinklers according to their materials. These sprinklers are suitable for irrigation of medium-sized green areas. Such as Anyou irrigation AY-5105 with 5 nozzles, has good spraying effect and ensures the uniform output of water flow in the spraying range.

Large range sprinklers are made of alloys, which ranges are above 20 meters. These characteristics are high strength and good impact resistance. In addition to large area irrigation, it is also suitable for mine dust removal system.

Permissible sprinkler irrigation intensity of soil is one of the main factors affecting sprinkler selection. Sprinkler irrigation intensity refers to the depth of water sprayed on the ground in unit time. Anyou irrigation generally considers the intensity of combined sprinkler irrigation, because the irrigation system is basically composed of multiple sprinklers working at the same time. The requirement of sprinkler irrigation intensity is that water can infiltrate into soil immediately after falling to the ground without puddles and surface runoff. That is to say, the combined sprinkler irrigation intensity (ρ combination) of sprinklers should be less than or equal to the water infiltration rate of soil. Reference values of permissible sprinkler irrigation intensity (ρ permissible) for all types of soils are shown in the table below.

The formula for calculating the intensity of combined sprinkler irrigation is as follows: ρ combination (mm/h) = 1000q/A. : ‘q’ is the flow rate of single sprinkler (m3/h); ‘A’ is the effective control area of single sprinkler (m²).

In addition, Anyou irrigation suggests, the permissible sprinkler irrigation intensity of soil decreased significantly with the increase of topographic gradient. If the slope is more than 12%, the permissible sprinkler irrigation intensity of soil will be reduced by more than 50%. Therefore, special attention should be paid to the selection of sprinkler head for the engineering of topographic fluctuation.

Sprinklers Arrangement in Sprinkler Irrigation System

The combination of sprinklers depends mainly on the shape of the plot and the influence of wind. Generally, they are rectangular and triangular, or they are special square and triangle. Rectangular or square layout is suitable for regular plots with right edges. The design of this form is simple and easy to make the flow of each branch pipe more balanced. The triangle or regular triangle layout is suitable for irregular plots or open plot boundaries, even if the spraying range exceeds part of the boundary, it has little influence. This arrangement has strong wind resistance, spraying uniformity is higher than rectangular or square, and the number of sprinklers used is relatively small, but it is not easy to make the flow of each branch pipe balanced. Sometimes the shape of the block is very complex, or there are obstacles in the block, so that the combination of sprinklers is irregular. When arranging sprinkler irrigation system, Anyou Irrigation suggests to uses square or triangle layout as far as possible.

When Anyou irrigation makes square arrangement, the distance between the sprinklers and the branch pipes is equal, but the distance between the sprinklers is 1.41 times of that between the branch pipes. Considering the influence of wind, the recommended distance between sprinklers is 0.9-1.1 times of  the range (R) of sprinklers, as shown in the table below.

The square arrangement of sprinklers by Anyou Irrigation

When the regular triangle is arranged, the distance between the sprinklers is equal, but the distance between the branches is 0.866 times as much as the distance between the sprinklers. Considering the influence of wind, Anyou irrigation recommends spacing of sprinklers is 1.0-1.2 times of the range (R) of sprinklers, as shown in the table below:

The triangle arrangement of sprinklers by Anyou Irrigation

After the sprinkler layout is completed, Anyou Irrigation suggests to check the combined sprinkler irrigation intensity of the system, according to the actual layout results. Especially in the corner area of the block, because the sprinkler is usually semi-circular or 90 degrees instead of full-circle sprinkler, if the selected nozzle is the same as the full-circle sprinkler in the middle of the block, the intensity of sprinkler irrigation in this area will be much higher than that in the middle of the block. Therefore, in order to ensure a good spraying uniformity of the system, the sprinklers installed in the corner should be equipped with 2-3 levels smaller than the sprinklers in the middle of the plot.